The present invention relates generally to a process and apparatus for producing low acid food products and, more particularly, but not by way of limitation, to a process and apparatus by which a naturally low acid food product can be acidified for storage and later de-acidified at the point of dispensing for consumption or freezing in suitable equipment.
The Code of Federal Regulations (xe2x80x9cCFRxe2x80x9d) governs many, if not most, aspects of food processing. Specifically, the CFR sets forth distinctions between xe2x80x9clow-acidxe2x80x9d foods and so called xe2x80x9cacidifiedxe2x80x9d foods. According to 21 CFR xc2xa7114.3, the phrase xe2x80x9clow-acid foodsxe2x80x9d means any foods, other than alcoholic beverages, with a finished equilibrium pH greater than 4.6 and a xe2x80x9cwater activityxe2x80x9d (aw) greater than 0.85. Low acid foods include milk, ice cream, creamers, and milk and/or vegetable fat containing beverages such as flavored cappuccino beverages. Special processing, packaging and handling of these products is necessary to prevent premature spoilage and the growth of microorganisms of public health significance. Current processing standards for unrefrigerated low acid foods require the application of a xe2x80x9cminimum thermal processxe2x80x9d with the application of heat to food, either before or after sealing in a hermetically sealed container, for a period of time and at a temperature scientifically determined to be adequate to ensure destruction of microorganisms of public health significance.
The phrase xe2x80x9cacidified foodsxe2x80x9d means low-acid foods to which acid(s) or acid food(s) are added and which have a water activity (aw) greater than 0.85 and have a finished equilibrium pH of 4.6 or below. These foods include cucumbers, cabbage, artichokes, etc. These foods may be called xe2x80x9cpickled.xe2x80x9d Acidity and salt levels are important factors retarding the growth and survival of bacteria and other microorganisms in acidified foods. Acidified food may be thermally processed, or processed with permitted preservatives to destroy vegetative cells of microorganisms of public health significance and to inhibit the reproduction of microorganisms of non-health significance.
Permitted chemical preservatives, pH and the water activity (aw) management of food products are important factors in extending food preservation beyond simple xe2x80x9cpickling.xe2x80x9d It is well known in the art that the combination of permitted preservatives, pH and water activity (aw) management of a food product can essentially prevent microbial growth. Water activity (aw) is defined as a measure of the free moisture in a product and is the quotient of the water vapor pressure of the substance divided by the vapor pressure of pure water at the same temperature. Water activity (aw) management is a beneficial preservation technique in cases when a bacterial cell comes in contact with a food product of relatively low water activity, such that the bacterial cell dehydrates, thereby inhibiting bacterial growth. Such dehydration of the bacterial cell occurs as a result of osmotic dehydration, during which time water transfer occurs between the food substance and the bacterial cell until equilibrium is reached, i.e., until both the food substance and the bacterial cell have the same water activity (aw). It is important to note that water activity (aw) is not proportional to moisture content of a substance. In fact, it is water activity (aw) and not moisture content that influences microbial growth. The challenge of food product design and formulation is to achieve relatively low water activity (aw) so that when the product comes in contact with bacterial cells, the level at which equilibrium is reached is low enough to inhibit almost all kinds of microbial growth. Therefore, it is essential in food chemistry to measure and monitor the water activity (aw) of a food substance as an aid in preventing spoilage.
Low acid food products require special processing, packaging and handling procedures (for example, aseptic processing and packaging; retort processing; or thermal processing with subsequent refrigeration), which add significantly to the cost of producing, distributing, and dispensing such low-acid food products. Acidified foods avoid much of these processing requirements and are, therefore, more economical to produce and store. Currently, a range of products such as non dairy creamers, frozen and iced cappuccino products, etc. are produced and are commercially viable only as low-acid foods. Low-acid versions (which are processed and packaged aseptically or are stored under refrigeration) are preferred by the market because of taste, texture and overall quality considerations. Acidified versions of these types of products suffer from poor taste and a lack of characteristic xe2x80x9cdairy flavor notesxe2x80x9d and creaminess that comes with fat, protein and other non-dairy solids.
Thus, efforts to develop high quality and shelf stable liquid concentrates that have xe2x80x9clow acid flavor profilesxe2x80x9d when reconstituted are a major objective of food and beverage companies, especially those who do not have aseptic processing capabilities.
The present invention comprises a method and apparatus for treating a low acid food product. The low acid food product is first acidified to produce an acidified food product and then packaged as the acidified food product. The acidifying step comprises addition of a GRAS acid to adjust the pH to below about 4.5. The acidified food product is then deacidified to return the acidified food product to the low acid food product having a pH above 4.6. The deacidification is accomplished through the addition of an alkaline substance in an amount sufficient to deacidify the acidified food product to a pH of from about 5.8 to about 7.5.
An automatic dispensing device for dispensing the acidified food product in its original low acid form comprises a water supply, an alklaine container containing an alkaline solution and a syrup container containing acidified syrup product. A pump operably connected to the syrup container pumps the acidified syrup product from the syrup container and into a mixing head. A vacuum switch operably connected between the syrup container and the pump disengages the automatic dispensing device when the syrup container is empty. The mixing head includes a single solenoid with a water input port, a syrup input port and an exit port for receiving and admixing the water and syrup product to create reconstitute. A venturi operably connected between the exit port and the alkaline container supplies the alkaline solution to the reconstitute through a metering solenoid. The metering solenoid is operably coupled to the venturi for metering the alkaline solution through the venturi to deacidify the reconstitute. A beverage tank receives the deacidified reconstitute and delivers the deacidified reconstitute as a beverage. A probe displaced within the beverage tank actuates the pump when the probe detects that the level of deacidified reconstitute is below a predetermined level.